Counterbalancing device for machine-tools.



S. H. BULLARD.

COUNTERBALANOING DEVICE FOR MACHINE TOOLS. APPLICATION FILED JAN.3,1911.

995,420, Patented June 13, 1911.

2 SHEETS-SHEET 1.

S. H. BULLARD.

GOUNTERBALANGING DEVICE FOR MACHINE TOOLS.

APPLICATION FILED JAN.3,1911.

' Patented June 13, 1911.

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STANLEY H. BULLARID, OF BRIDGEPORT, CONNECTICUT, ASSIGNOR TO THE BULLARD MACHINE TOOL 00., OF BRIDGEPORT, CONNECTICUT, A CORPORATION OF CON- NECTICUT.

COUNTERBALANCING DEVICE FOR IMACHINE-TOOLS.

Specification of Letters Patent.

Patented June 13, 1911.

To all whom it may concern:

Be it known that 1 STANLEY H. BULLAim, citizen of the United States, and resident of Bridgeport, in the county of Fail-field and State of Connecticut, have invented certain new and useful Improvements in Counterbalancing Devices for Machine- Tools, of which the following is a specification.

This invention relates to improvements in counterbalancing devices for machine tools, such for instance boring mills, lathes, maxi-mills and the like, and refers particularly to means for counterweighting the vertically operatin slide carried on the cross rail designed to support the tool head.

It is the object of the invention to provide an improved form of counter-balancing mechanism including a wire rope or chain and a series of connected weights, in such a manner that a maximum movement of the head may be effected with but a minimum movement of the weight, and whereby the cross rail to which the head slide is at tached may be adjusted vertically without effecting the position of such weights; to provide a separate and independent counterweighting mechanism for each head-slide carried on the rail, and finally to arrange the parts so that one end of the rope or chain will be attached to the frame of the machine, and the other end the weights, the intermediate portions being passed over suitable guide wheels so placed and arranged as to insure an easy adjustment of the parts.

lpon the accompanying drawings forming a part of this specification, similar characters of reference will be found to denote like or corresponding parts throughout the several figures and of which- Figure 1, shows an incomplete front view of an improved type of boring mill, including a cross rail, and head slide, and fitted with my improved counterbalancing device. Fig. 2, is a side View of the machine shown in Fig. l and Fig. 3, is a detail vertical cross sectional view of the cross rail and attached parts, shown in Fig. 1 and taken on line 3 3 of said figure.

Referring in detail to the characters of reference marked upon the drawings, 5 indicates the base of a boring mill to which my invention is shown applied.

6 represents column secured to the base and to the face of which a cross rail 7 is adjustably attached.

8 represents a work carrying table rota tably mounted in the forward portion of the base before mentioned. The cross rail 7 mounted upon the faces of the columns (3, is made adjustable, vertically thereon, by means of screws 9 carried in the uprights and operated in any suitable manner.

Upon the cross rail 7, is mounted one or more saddles 10, according to the number of heads used upon the machine; there being two shown in the present instance, one to traverse the face of each side portion of the rail, or that is, that part of the rail. intermediate of its center, and its end portions. A slide 11 is mounted in each of these saddles, and designed to support the usual form of tool head, not shown, but usually secured to the lower end of such slides for supporting the tools that operate upon the work carried by the rotary table 8 above mentioned. Each of these slides are provided with a rack 12, for engagement with a small gear, not shown, but through which the slide is vertically adjusted. It is with a view of counterbalai'icing the weight of these slides and heads carried thereon, that I have provided my novel form of counterweighting device, and as above stated, said counterbalancing mechanism for each slide is separate from the other, though alike in construction; therefore a detail description of the one will suflice for both. lVhilc I shall refer to the connection intermediate of the slide and weight as a rope, yet it will be understood that this can be formed of wire or be made of chain, as preferred.

Referring to Figs. 1 and 2 it will be seen, that one end of this rope 13 is secured to the inner side of the column as at 13, forming a fixed connection to a stationary part of the frame of the machine, and notto the movable rail as has heretofore been the case. This rope is first taken up from the point 13, and over and under guide wheels 14, 15 and 16, arranged adjacent to each other, and journaled upon studs of a bracket 17, attached to the cross rail. The rope is then carried across to the other side of the machine, and next deflected over a guide pul ley 18, secured to the saddle, and then down under and around a further guide pulley 19, operatively mounted upon the lower end portion of the slide 11, and whereby the slide is supported. The rope is next returned upon the opposite side and carried over a second guide wheel 20 journaled upon the before mentioned stud of the saddle and then carried out around a horizontally arranged guide wheel 21, operatively attached to the outer end of the top portion of the cross rail. The rope is next returned in a horizontal plane and carried around the near by wheel 22, secured to the cross rail, and then disposed up, over and around a pair of guide wheels .23, mounted upon a bracket attached to the top of one of the side members of the column of the frame. The end of the rope is finally directed down into an elongated pocket 24 of the column, and there provided with a series oi weights 25, suflicient to tightly draw the rope over the several wheels and against the resistance of the pin 13, and the weight of the slide 11 in a manner to support the same.

From the foregoing construction it will be noted, that any vertical movement of the rail 7, does not materially change the position of the weights, and that an adjustment of the slide itself, only serves to move the weight a comparatively short distance within the pocket. The weight being inclosed in the manner shown, it is entirely out of the way, and its change of position is not noticed nor does the possible breakage of such rope or chain endanger the operator. lVhen a double headed mill is to be fitted with the improved counterbalancing device, I preferably locate the weight of the one slide in the opposite side member of the column and that for the other slide in the side member of the column directly back of the first mentioned slide, in the manner indicated in the drawings.

Having thus described my invention, what I claim and desire to secure by Letters Patent is,

1. The combination with suitable columns of a machine, a vertically adjustable cross rail, a saddle upon the rail and a slide mounted in the saddle, of guide wheels mounted upon each of said columns, cross rail, saddle and slide, a rope one end of which is fixed to the column and passed over the guide wheels on the rear side of the rail, then over the wheels of the saddle upon their end, next over the guide wheel of the slide and finally over another wheel upon the rail and wheel of the saddle and column, and a weight attached to the end of the rope and contained within the pocket of the column.

2. The combination with suitable columns of a machine, having a pocket therein, a vertically adjustable cross rail, a saddle upon the rail and a slide mounted in the saddle, of a rope one end of which is secured to the column and then passed over guidesof the rail on one side and guides of the saddle upon the other side, a guide upon the slide, a guide upon the end of the cross rail and finally over another guide of the saddle and upon the column, and a weight upon the end of the rope disposed within the pocket of the column.

3. The combination with suitable columns of a machine, a vertically adjustable cross rail, a saddle upon the rail and a slide mounted in the saddle, of a rope one end of which is secured to the column, guide wheels upon the cross rail over which the rope passes, a guide wheel upon the slide, a pair of guide wheels upon the saddle above the wheel on the slide and over which the rope is passed to and from the wheel of the slide, and additional guide wheels upon the outer end portion of the rail and the saddle, and on top of the column and over which the rope is passed, and a weight attached tr the free end of the said rope.

4:. In a counterbalancing device for machine tools, the combination with a pair of columns arranged apart from each other, a cross rail mounted thereon, a saddle upon the cross rail, and a vertically adjustable slide mounted in the saddle, of a rope one end of which is fixed to one of the columns and then threaded over guides of the rail, saddle and slide in a manner to adjustably support the slide with relation to the saddle, and having the end of said rope disposed in a pocket of the said second column on the opposite side of the machine, and a weight attached to the said free end of the rope.

Signed at Bridgeport in the county of Fairfield and State of Connecticut this 28th day of December A. D. 1910.

STANLEY I-I. BULLARD.

lVitnesses E. P. BULLARD, Jr., .C. M. NEWMAN.

Copies of this patent may be obtained for five cents each, by addressing the Commissioner of Eatents.

Washington, D. C. 

